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The present study evaluated whether fat mass assessment using the triceps skinfold (TSF) thickness provides additional prognostic value to the Global Leadership Initiative on Malnutrition (GLIM) framework in patients with lung cancer (LC). We performed an observational cohort study including 2672 LC patients in China. Comprehensive demographic, disease and nutritional characteristics were collected. Malnutrition was retrospectively defined using the GLIM criteria, and optimal stratification was used to determine the best thresholds for the TSF. The associations of malnutrition and TSF categories with survival were estimated independently and jointly by calculating multivariable-adjusted hazard ratios (HR). Malnutrition was identified in 808 (30·2 %) patients, and the best TSF thresholds were 9·5 mm in men and 12 mm in women. Accordingly, 496 (18·6 %) patients were identified as having a low TSF. Patients with concurrent malnutrition and a low TSF had a 54 % (HR = 1·54, 95 % CI = 1·25, 1·88) greater death hazard compared with well-nourished individuals, which was also greater compared with malnourished patients with a normal TSF (HR = 1·23, 95 % CI = 1·06, 1·43) or malnourished patients without TSF assessment (HR = 1·31, 95 % CI = 1·14, 1·50). These associations were concentrated among those patients with adequate muscle mass (as indicated by the calf circumference). Additional fat mass assessment using the TSF enhances the prognostic value of the GLIM criteria. Using the population-derived thresholds for the TSF may provide significant prognostic value when used in combination with the GLIM criteria to guide strategies to optimise the long-term outcomes in patients with LC.
The retention of patients under methadone maintenance treatment (MMT) is an indication for the effectiveness of the therapy. We aimed to explore the relation between mortality and the cumulative MMT duration.
A retrospective cohort analysis was performed using Taiwan Illicit Drug Issue Database (TIDID) and National Health Insurance Research Database (NHIRD) during 2012–2016. We included 9149 and 11 112 MMT patients as the short and long groups according to the length of their cumulative MMT duration, 1–364 and ⩾365 days, respectively. The risk of mortality was calculated by Cox proportional hazards regression model with time-dependent exposure to MMT, and the survival probability was plotted with the Kaplan-Meier curve.
The mortality rates were 2.51 and 1.51 per 100 person-years in the short and long cumulative MMT duration groups, respectively. After adjusting for on or off MMT, age, sex, marital status, education level, maximum methadone dose, and comorbidities (human immunodeficiency virus, depression, hepatitis C virus, hepatitis B virus, alcoholic liver disease, and cardiovascular disease), the long group had a lower risk of death (hazard ratio = 0.67; 95% confidence interval 0.60–0.75) than the short group. Increased risk was observed in patients with advanced age, being male, unmarried, infected by HIV, HCV, and HBV, and diagnosed with depression, ALD, and CVD. Causes of death were frequently related to drug and injury.
Longer cumulative MMT duration is associated with lower all-cause and drug-related mortality rate.
Over recent decades, Chinese giant salamanders Andrias spp. have declined dramatically across much of their range. Overexploitation and habitat degradation have been widely cited as the cause of these declines. To investigate the relative contribution of each of these factors in driving the declines, we carried out standardized ecological and questionnaire surveys at 98 sites across the range of giant salamanders in China. We did not find any statistically significant differences between water parameters (temperature, dissolved oxygen, ammonia, nitrite, nitrate, salinity, alkalinity, hardness and flow rate) recorded at sites where giant salamanders were detected by survey teams and/or had been recently seen by local respondents, and sites where they were not detected and/or from which they had recently been extirpated. Additionally, we found direct and indirect evidence that the extraction of giant salamanders from the wild is ongoing, including within protected areas. Our results support the hypothesis that the decline of giant salamanders across China has been primarily driven by overexploitation. Data on water parameters may be informative for the establishment of conservation breeding programmes, an initiative recommended for the conservation of these species.
Interception by plant canopies during wind dispersal can affect the final destination of diaspores. However, how the interaction of wind speed, canopy type and diaspore attributes affects interception of diaspores by the plant canopy has rarely been studied. We investigated canopy interception for 29 species with different diaspore attributes, six canopy types and six wind speeds in controlled experiments in a wind tunnel. Shrub canopy interception of diaspores were controlled by wind speed and diaspore attributes, but the latter had a greater influence on canopy interception than the former. At low wind speed, diaspore wing loading had a large influence on canopy interception, whereas at high wind speed, diaspore projection area had a large influence. The chance of canopy interception at a particular wind speed was additionally affected by the type of canopy. This study increases our knowledge of the dispersal process, corrects the previous understanding of diaspore dispersal potential and improves the theoretical basis for predicting spatial pattern and dynamics of plant populations.
The orientation between twin boundary (TB) and loading direction may play an intriguing role in the deformation behaviors of twinned metallic materials. In this aspect, its essential effect on the high-entropy alloy (HEA) nanocrystals is elusive. Attention herein is focused on the atomic-scaled deformation mechanisms and fracture behaviors of HEA nanocrystals containing twins of even smaller spacings via a combined approach of in situ tensile tests inside a high-resolution transmission electron microscope and molecular dynamics simulations. The results indicate that the deformation mechanisms (especially dislocation activities) of HEA nanocrystals depend on the load orientation with respect to TBs. Because of the low activation energy and uneven local composition of HEA, the surface acts as an effective dislocation source and, together with Schmid factor, dominate the activated dislocation slip system. The load orientation-dependent TB-dislocation interactions may transform the type of fracture from semi-brittle to ductile. Our results indicate that the deformation mechanisms and the types of fracture in HEA nanocrystals can be controlled by changing the orientation.
There has been considerable interest in stratospheric airships as a cost-effective alternative to earth orbit satellites for sightseeing, aerial photography, communication and carrying weapons, etc. Many countries have plans to develop the airship owing to its greatly expected usage. The suspended curtain plays a vital role in force transmission in stratospheric airships but lacks attention. In this paper, the relationship between the optimal shape of suspended curtain and load conditions was studied through CAE Abaqus and Isight. Firstly, by using secondary development function of Abaqus, parametric FEA models of suspended curtains and envelopes have been established, several parameters were used to describe the shape of suspended curtains. Secondly, parameters of the suspended curtain shape were optimized under different loading conditions by means of the genetic algorithm. Lastly, through the analysis of the results, some conclusions are summarized: The relationship between n1(n2) and nb was found to be linear when the suspended curtain is subjected to vertical load. The stress transfer law of suspended curtain and inflatable membrane structure under the inclined load were also obtained, which are valuable for the structural engineering design of stratospheric airships..
As China implements the voluntary vaccination programme of one-dose of varicella vaccine (VarV) for decades, robust estimates of the impact of voluntary vaccination era on epidemiology of varicella are needed. We estimated the vaccination coverage (VC) of VarV by using surveillance data on immunisation. The descriptive epidemiological method was used to describe the changing epidemiology of varicella from 2007 to 2018. The screening method was used to estimate the vaccine effectiveness (VE) of VarV. The overall VC for VarV was 71.7%, ranged from 47.7% to 79.5% among 2008–2017 birth cohorts. In total, 16 660 varicella cases were reported during 2007–2018, the incidence increased from 10.0 cases per 100 000 population in 2007 to 65.2 cases per 100 000 population in 2018. A shift in age group of varicella was observed since 2012, with the age increased from 5–9 years to 10–14 years. The overall VE was 79.9%, and the VE increased from 60.1% in 2008 birth cohort to 96.2% in 2017 birth cohort. We found that the overall VE for VarV is moderate, but appears highly effective within 5 years after vaccination. In addition, a shift varicella infection to older ages has occurred at the long-term moderate level VC of one-dose VarV. Therefore, to contain the incidence of varicella and prevent any potential shift to older ages, the introduction of VarV into routine immunisation programme is likely needed in Lu'an.
Ta–W co-alloying was realized by double glow plasma surface metallurgy technology, and their effects on high-temperature oxidation behavior of γ-TiAl were studied. Ta–W co-alloying coating was composed of a deposited layer and interdiffusion layer. The results of isothermal oxidation experiment indicated that a compact mixed oxide film of Ta and W was formed on the sample. The interdiffusion layer reduced the oxygen intrusion that improved the high-temperature oxidation resistance of γ-TiAl. The effects of Ta–W co-alloying on oxygen adsorption energy and electronic structure of γ-TiAl(111) were analyzed by first-principle calculation. The results showed that the optimal adsorption sites of O atoms changed from fcc-Al to hcp-Ti and hcp-Al, indicating that Ta–W co-alloying inhibited the diffusion of O. The electronic structure analysis of γ-TiAl(111) after Ta–W alloying indicated the affinity of Ti and O was inhibited, which resulted in decreased TiO2 in the oxide film.
A simple, compact, double-pass pumped Nd:YVO4 thin disk laser is demonstrated. Its continuous-wave performance with different Nd doping concentrations and thicknesses is investigated experimentally. The maximum output power of 17.7 W is achieved by employing a 0.5 at.% doped sample, corresponding to an optical-to-optical efficiency of 46% with respect to the absorbed pump power. In addition, a numerical analysis and an experimental study of the temperature distribution, and thermal lens effect of the Nd:YVO4 thin disk, are presented considering the influence of the energy transfer upconversion effect and the temperature dependence of the thermal conductivity tensor. The simulated results are in good agreement with the experimental results.
We present details of on-wafer-level 16-term error model calibration kits used for the characterization of W-band circuits based on a grounded coplanar waveguide (GCPW). These circuits were fabricated on a thin gallium arsenide (GaAs) substrate, and via holes, were utilized to ensure single mode propagation (i.e., eliminating the parallel-plate mode or surface mode). To ensure the accuracy of the definition for the calibration kits, multi-line thru-reflect-line (MTRL) assistant standards were also fabricated on the same wafer and measured. The same wafer also contained passive and active devices, which were measured subject to both 16-term and conventional line-reflect-reflect-match calibrations. Measurement results show that 16-term calibration kits are capable of determining the cross-talk more accurately. Other typical calibration techniques were also implemented using the standards on the GCPW calibration kits, and were compared with the MTRL calibration using a passive device under test. This revealed that the proposed GCPW GaAs calibration substrate could be a feasible alternative to conventional CPW impedance standard substrates, for on-wafer measurements at W-band and above.
Guangxi, a province in southwestern China, has the second highest reported number of HIV/AIDS cases in China. This study aimed to develop an accurate and effective model to describe the tendency of HIV and to predict its incidence in Guangxi. HIV incidence data of Guangxi from 2005 to 2016 were obtained from the database of the Chinese Center for Disease Control and Prevention. Long short-term memory (LSTM) neural network models, autoregressive integrated moving average (ARIMA) models, generalised regression neural network (GRNN) models and exponential smoothing (ES) were used to fit the incidence data. Data from 2015 and 2016 were used to validate the most suitable models. The model performances were evaluated by evaluating metrics, including mean square error (MSE), root mean square error, mean absolute error and mean absolute percentage error. The LSTM model had the lowest MSE when the N value (time step) was 12. The most appropriate ARIMA models for incidence in 2015 and 2016 were ARIMA (1, 1, 2) (0, 1, 2)12 and ARIMA (2, 1, 0) (1, 1, 2)12, respectively. The accuracy of GRNN and ES models in forecasting HIV incidence in Guangxi was relatively poor. Four performance metrics of the LSTM model were all lower than the ARIMA, GRNN and ES models. The LSTM model was more effective than other time-series models and is important for the monitoring and control of local HIV epidemics.
Whether borderline personality disorder (BPD) and bipolar disorder are the same or different disorders lacks consistency.
To detect whether grey matter volume (GMV) and grey matter density (GMD) alterations show any similarities or differences between BPD and bipolar disorder.
Web-based publication databases were searched to conduct a meta-analysis of all voxel-based studies that compared BPD or bipolar disorder with healthy controls. We included 13 BPD studies (395 patients with BPD and 415 healthy controls) and 47 bipolar disorder studies (2111 patients with bipolar disorder and 3261 healthy controls). Peak coordinates from clusters with significant group differences were extracted. Effect-size signed differential mapping meta-analysis was performed to analyse peak coordinates of clusters and thresholds (P < 0.005, uncorrected). Conjunction analyses identified regions in which disorders showed common patterns of volumetric alteration. Correlation analyses were also performed.
Patients with BPD showed decreased GMV and GMD in the bilateral medial prefrontal cortex network (mPFC), bilateral amygdala and right parahippocampal gyrus; patients with bipolar disorder showed decreased GMV and GMD in the bilateral medial orbital frontal cortex (mOFC), right insula and right thalamus, and increased GMV and GMD in the right putamen. Multi-modal analysis indicated smaller volumes in both disorders in clusters in the right medial orbital frontal cortex. Decreased bilateral mPFC in BPD was partly mediated by patient age. Increased GMV and GMD of the right putamen was positively correlated with Young Mania Rating Scale scores in bipolar disorder.
Our results show different patterns of GMV and GMD alteration and do not support the hypothesis that bipolar disorder and BPD are on the same affective spectrum.
The excessive use of plastic, especially polystyrene (PS), has caused serious environmental pollution. The efficient utilization of plastics and the conversion of plastics into value-added carbon materials are the concerns of researchers. Herein, we propose novel “pyrolysis–deposition” method to convert one popular plastic substance, PS, into ordered mesoporous carbons (OMCs). During the synthesis process, PS is pyrolyzed into small organic gases under high temperature, which is then adsorbed through capillary adsorption into the mesoporous of SBA-15 in the presence of catalyst. The obtained OMCs have high specific surface area, uniform pore size, and ordered pore structure. The OMCs exhibit specific capacitance of 118 F/g at a current density of 0.2 A/g and electrochemical stability of 87.2% at a current density of 2 A/g after 5000 cycles. The pyrolysis–deposition strategy provides a new idea to convert waste plastics into high-performance carbon materials for electrochemical applications.
Direct determination of barrier height (ΦBH) value between Ir and single crystal (001) hydrogen-terminated diamond with lightly boron doped has been performed using x-ray photoelectron spectroscopy technique. 70 nm Ir islands were formed on hydrogen-terminated diamond surface using anodic aluminum oxide. The ΦBH value for Ir/hydrogen-terminated diamond was −0.43 ± 0.14 eV, indicating that Ir was a suitable metal for ohmic contact with hydrogen-terminated diamond. The band diagram of Ir/hydrogen-terminated diamond was obtained. The experimental ΦBH was compared with the theoretical ΦBH in this work.
We report on a high-repetition-rate, high-power continuously pumped Nd:GdVO4 regenerative amplifier. Numerical simulations successfully pinpoint the optimum working point free of bifurcation instability with simultaneous efficient energy extraction. At a repetition rate of 100 kHz, a maximum output power of 23 W was obtained with a pulse duration of 27 ps, corresponding to a pulse energy of
. The system displayed an outstanding stability with a root mean square power noise as low as 0.3%. The geometry of the optical resonator and the pumping scheme enhanced output power in the
mode with a single bulk crystal. Accordingly, nearly diffraction-limited beam quality was produced with
at full pump power.
Ti/Al/Mg/Al/Ti laminates were fabricated by hot rolling at 450 °C with various rolling reductions, and the relationship between the mechanical properties and microstructures was investigated in detail. Both Al–Mg and Ti–Al interfaces are well bonded without pore, crack, and intermetallics. Mg layer of 50% rolling reduction has the most dynamic recrystallized (DRXed) grains around the deformation bands, and tensile twins appear in Mg layer when the rolling reduction increases to 60%. Large numbers of twins are formed to absorb the further strain as reduction increases. Ti layer shows equiaxed grains, which are not sensitive to thickness strain. Mg layers of laminates with various rolling reductions all exhibit typical (0002) basal texture. Fifty-percent rolling reduction has the largest ultimate tensile strength of 337.8 MPa, which is mainly owing to grain refinement caused by the extensive DRX. The differences of elongation among the three samples with different rolling reductions are small.
Nanosize SiCp (n-SiCp) reinforced Mg–9Al matrix composites (Mg–9Al–xSiC, x = 2.5, 5, 7.5, 10 wt%) with nearly full densification are fabricated by the semisolid powder hot pressing technique assisted with ultrasonic. The effect of SiC nanoparticle contents on microstructures and mechanical properties of the composites is systematically investigated. Grain size and density of Mg–9Al–xSiC composites and morphology of bonding interfacial between the n-SiCp and matrix are found to be greatly dependent on the n-SiCp contents, resulting in the strength and ductility of the composites increase first and then decrease as the increase of n-SiCp contents. As the SiCp content increasing to 7.5 wt%, superior mechanical properties with the yield strength of 191 MPa, ultimate tensile strength of 248 MPa, and elongation to failure of 5.3% are achieved. The improved mechanical properties could be attributed to grain boundary strengthening, Orowan strengthening, and load transfer strengthening.
The effect of equal-channel angular pressing (ECAP) at various temperatures (310, 330, and 350 °C) on precipitations and strengthening mechanisms of Mg–9Al–1Si alloys was investigated. The results indicated that the average grain size decreased gradually with decreasing of ECAP temperature. The distribution of the Mg2Si phase changed a little when the ECAP temperature increased. However, the different morphologies of β-Mg17Al12 phase were observed, including continuous and uncontinuous precipitation of particles at 310 and 350 °C. The continuous β-Mg17Al12 phase was hardly found and the refined β-Mg17Al12 phase was distributed dispersedly in the matrix at 330 °C. Thus, the mechanical properties of the Mg–9Al–1Si alloy was optimum: ultimate tensile strength and elongation were ∼350.8 MPa and ∼14.77%, respectively. It can be deduced that both grain refinement strengthening and precipitation strengthening play significant roles in strength increment of the alloy during the ECAP process. However, precipitation strengthening is the predominant mechanism.
To obtain a fine-grained Mg matrix, the (submicron + micron) bimodal size SiC particle reinforced AZ91 (SiCp/AZ91) composite was subjected to forging followed by the extrusion process first. Then, the fine-grained bimodal size SiCp/AZ91 composite was compressed at 270–370 °C with 0.1–0.001 s−1. The result indicated that the refinement of the Mg matrix contributed to its deteriorated strength at high temperature. However, the grain size is not the only factor influencing flow stress but the SiCp also plays an important role. The effect of SiCp on the fine grained Mg matrix depends on grain size and dislocation density, both of which strongly depend on temperature and strain rate. As compared with the fine grained Mg matrix reinforced by single size SiCp, the one with bimodal size SiCp unusually exhibit lower flow stress during hot compression. The calculated activation energy of the bimodal size SiCp/AZ91 composite is higher than the micron SiCp/AZ91 composite; however, nearly the same as the submicron SiCp/AZ91 composite, and the deformation of which was thought to be controlled by ∼1 vol% submicron SiCp.